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971.
The clinical, biochemical and pathological features of 31 patients with thyroid carcinoma managed at Hospital Universiti Sains Málaysia, Kubang Kerian from 1985 to 1989 were analyzed. There were 25 females and 6 males. The types of carcinoma were: papillary-17 cases; follicular-10 cases; medullary-2 cases and anaplastic-2 cases. For papillary carcinoma the mean age of the patients was 52.9 years. For follicular carcinoma the mean age was 48.3 years, for medullary carcinoma, 48.5 years and for anaplastic, 74.5 years. All patients had pre-existing goitre except for 2 and most presented with advanced disease. The mean duration of symptoms for papillary carcinoma was 3.7 years, follicular carcinoma 1.6 years, medullary carcinoma 13.5 years and anaplastic carcinoma 6 months. 12 patients presented with goitre of increasing size; 9 had compression symptoms; 4 presented with cervical lymph node enlargement and 6 presented with bony pains of whom 2 had paraplegia. None of the patients were ever thyrotoxic or hypothyroid. Treatment in general was unsatisfactory because of patients' non-acceptance of surgery and/or radioactive iodine.  相似文献   
972.
973.
The effects on seizures, EEG and behavior of the non-NMDA receptor antagonist CNQX (6-cyano-7-nitroquinoxaline-2,3-dione), were studied in the WAG/Rij rat with absence epilepsy. Intracerebroventricular injections (10, 50, and 100 nmol/5 microliters CNQX) showed that CNQX decreases the number of spike wave discharges in a dose-dependent way. Coinjection of CNQX (100 nmol/5 microliters) and AMPA (0.1 pmol/5 microliters), kainic acid (0.01 nmol/5 microliters) or NMDA (50 pmol/5 microliters) attenuated the CNQX response, indicating that CNQX acts on both non-NMDA and NMDA receptors. The observed effects appear to be specific manipulations of the epilepsy not mediated by behavioral changes.  相似文献   
974.
975.
976.
Summary A false-negative finding on initial CT is reported in a case of supratentorial glioma. This observation was peculiar because the first CT revealed a meningioma which might initially have been related to the clinical symptoms. The term false positive-false negative CT is proposed. The reasons for such CT failures are discussed. The accuracy of clues as to the localization of the glioma provided by EEG is emphasized.  相似文献   
977.
978.
The isolated azygos continuation of the inferior vena cave is a very rare variation of this organ. It is accompanied by the absence of the retrohepatic segment of the vena cava with two new observations, the literature is revised and the origin discussed.  相似文献   
979.
The effects of five minutes of wrist flexion on median motor and sensory evoked potential latencies in 87 individuals were studied. Nineteen subjects had carpal tunnel syndrome (CTS) as diagnosed by increased median nerve latencies across the wrist, and 68 had values in the normal range and were assigned to the control group. A slight prolongation of up to 0.5m sec of evoked potential latencies was observed in both groups after flexion, but the differences between the two groups were not significant to establish the value of adding wrist flexion to conventional screening methods.  相似文献   
980.
The aim of the current study was to investigate the in-vitro and in-vivo performance of a press-coated tablet (PCT) intended for time delayed drug release, consisting of a rapidly disintegrating theophylline core tablet, press-coated with barrier granules containing glyceryl behenate (GB) and low-substituted hydroxypropylcellulose (L-HPC). The PCTs showed pulsatile release with a lag time dependent upon the GB and L-HPC composition of the barrier layer. In-vivo gamma-scintigraphic studies were carried out for PCTs containing GB:L-HPC at 65:35 w/w and 75:25 w/w in the barrier layer in four beagle dogs, in either the fed or fasted state. The in-vivo lag time in both the fed and fasted states did not differ significantly (p>0.05) from the in-vitro lag time. Additionally, no significant difference (p<0.05) between in-vivo fed and fasted disintegration times was observed, demonstrating that in-vivo performance of the PCT was not influenced by the presence or absence of food in the gastrointestinal tract. A distinct lag time was obtained prior to the appearance of drug in plasma and correlated (R2=0.98) with disintegration time observed from scintigraphic images. However, following disintegration, no difference in pharmacokinetic parameters (AUC(0-6 dis), K(el), Cmax) was observed. The current study highlighted the potential use of these formulations for chronopharmaceutical drug delivery.  相似文献   
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